共沉淀-γ辐射合成Fe_3O_4纳米晶体  

Synthesis of Fe_3O_4 nanocrystals by coprecipitation-gamma radiation

作　　者：胡晓丹[1] 张海黔[1] 周小虎[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,江苏南京210016

出　　处：《江苏大学学报（自然科学版）》2010年第6期674-677,共4页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(20975052);江苏省自然科学基金资助项目(SBK200922574)

摘　　要：分别以聚乙二醇、聚乙烯吡咯烷酮作分散剂,将共沉淀法与γ辐射相结合,合成了纳米四氧化三铁.以透射电子显微镜、XRD粉末衍射仪、傅立叶红外光谱仪、振动样品磁强计对制备的纳米晶体形貌、结构、磁性能进行了分析,同时初步讨论了纳米Fe3O4的形成机理.结果表明：聚乙二醇、聚乙烯吡咯烷酮作为高分子分散剂,产生空间位阻效应,避免颗粒团聚;四氧化三铁纳米晶体具有立方体结构,高能射线引入纳米材料的合成,有利于改善纳米粒子的形貌结构;与传统的共沉淀方法比较,γ射线改善了纳米粒子的结晶性、分散性,粒径约在5-20 nm范围;在γ射线辐照条件下,磁性能发生变化,比饱和磁化强度明显下降,矫顽力基本保持不变.Fe3O4 nanocrystals were synthesized by coprecipitation-gamma radiation with polyethylene glycol or polyvinyl pyrrolidone as dispersant.Fe3O4 nanocrystals were characterized in order to elucidate the morphology,structure and magnetism by transmission electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy and vibrating sample magnetometer respectively.The formation mechanism of Fe3O4 nanocrystals was also studied.The results indicate that polyethylene glycol and polyvinyl pyrrolidone can produce steric effect to avoid agglomeration of particles as polymeric dispersants.Fe3O4 nanocrystals are cubic phase and high-energy radiation favours the improvement of morphology.The crystallinity and dispersity of nano-particles are improved by gamma radiation compared with the particles obtained by traditional coprecipitation.The sizes of Fe3O4 nanoparticles are in the range of 5~20 nm.The magnetic properties change markedly under γ-radiation.The saturation magnetization obviously decreases and the coercive force of the nanoparticles change very little.

关 键 词：四氧化三铁 共沉淀 Γ辐射 合成 纳米晶体 

分 类 号：O614.811[理学—无机化学] O644.22[理学—化学]